Holographic waveguide display

A holographic waveguide display comprises: a source of light; at least one switchable grating layer comprising a multiplicity of grating regions each switchable between a diffracting state and a non diffracting state; means for spatio-temporally modulating light from the source to provide image light comprising at least one beam deflector for scanning the light in at least one of two orthogonal directions and at least one modulator for amplitude modulating the light. A first scanned angular range of light is diffracted through a first area into a first field of view by a first set of grating regions, and through a second area into to the first field of view by a second set of grating regions. Each grating region of the first and second sets has a first grating function. The first and second areas lie within an exit pupil of the display.